Electric horn



Aug? 24 1926, 1,597,501

B. AMES ET A L ELECTRIC HORN Fiied Jan. Q, 1922 Figa' Patented Aug. 24, 1926.

BUTLER AMES AND PHILIP J'. GILNSN,

FFW..

Dl? LOVELL, MASSACHUSETTS, ASSIGNORS TO HEINZ ELECTRIC COMPANY, OF LGWELL, hASSAC-USETTS,A CQRPORATON 0F MAINE.

Pipplcaticn filed January rl`liis invention relates to. signal horns oi' the electrically operated diaphragm type, particularly adapted to be used upon motor vehicles to give timely warning of their appreach.

ln order to be acceptable to the trade, a device ci this character should bev compact in form, light in weight, of substantial and durable construction, relatively low in iirst cost and upkeep, should be reliable and unailing in operation, and should emit a signal tone ci pleasing character. While numerous attempts have been made to improve such devices, any changes made with the purpose et battering such a device in one particular, have commonly resulted injuriously as respects other parts or properties of 'the device. rhis is particularly true when changes ier the purpose of cheapening the device or making it more compact or light in weight have been attempted, as in mest such cases the sound emitted by the horn has been made raucous and unpleasantthereby ren-` dering the horn of little commercial value. ln order to produce a true musical tone, it is essential that the striker vibrate with a predete 1mined velocity and amplitude. Any looseness or play between the supporting parts or any failure of the circuit breaker properly to Afunction leads however, to the production of a confused noise havinglittle carrying power and of decidedly disagreeable acoustic quality. For best results moreover, the natural period of vibration of the vibratiiipparts should approximate that of the diaphragm and when attempts have been made heretofore to devise signals of compact form, this feature has been sacrificed altogether.

The principal objects of the present invention are accordingly, to provide a signal of compact and durable type, light in weight and simple of construction, while at the same time providing rigid supporting means for the movable parts whereby the action of the latter may accurately be predetermined,so constructed as to permit of the employment of a striker supporting spring having the desired amplitude of vibration, and employingelectrical contact elements capable of accurate adjustment. In accordance with the present invention the above objects are attained by providing a base 9, 1522. Serial N0. 527,991.

plateor cover for the diaphragm and securing directly to said base plate, or to a frame tiredly secured thereon, all the various parts ot the operating mechanism. Preiterably the (frame referred to comprises oppositely diverging arms to the outer ends of which the armature supporting spring is secured. This arrangement permits of the employment of a spring of a length substantially equal to the diameter of the diaphragm and by properly determining the resiliency orn such spring an amplitude oi vibration substantially equal to that of the diaphragm may be readily attained. The armature and striker are rigidly secured to such spring, the striker however, being adjustable to permit of determining its initial position as respects the diaphragm. The contact making and breaking devices are carried upon a bracket integrally secured to the base plate and such centact making and breaking devices are arranged 'for relative adjustment whereby great accuracy in operation may be attained. Suitable securing means are provided whereby undesirable relative movement or parts may be eliminated, the whole device being of a very simple construction and cheap to manufacture. ln securing the supporting trame to the base plate, advantage is taken ot the presence of the magnet cores, which are eX- tended through openings in the frame and base plate and are headed over on the under side of the latter. The base plate, frame, and magnets are thus rigidly and permanently connected so that no looseness can develop between these parts. The movement of the armature through its predetermined path' is thus substantially assured and although most ot the parts, including the base plate and frame are made from sheet metal stampings, the signal is sulliciently rigid to withstand rough usage and the vibration and shocks to which a device of this char-l acter is commonly subjected.

In the accompanying drawings there is illustrated by way of example, a preferred embodiment of the device whereby the above objects may be attained, and in such drawings,-

F ig. l is an end elevation with the cap removed to show the interior mechanism;

Fig. 2 is a section on the line 2-2 ol` Fig. l;

Fig. 3 is a section on the line 3 3 of Fig. 1;

Fig. 4 is a perspective view of a clip for holding the armature; n

Figs. 5 and 6 are, respectively, side and end elevations of one of the contact members; and

F ig.7 isa perspective view of the other contact member.

The embodiment of the invention s'no'wn for the purpose of illustration is -an electrically operated signal comprising a horn 8 which is'expanded at the rear andprovided with a circumferential flange 9V defining-a recess in which are received a diaphragm 10 and a base plate 11, the latter being spaced from ythe diaphragm by an annular washer 10a. These parts-are preferably.permanently united in any suitable manne-r, as by rivets 13CL and bolts 14a. Certain of the bolts and rivetspass through a bracket ln'by which the signal is conveniently mounted upon a vehicle. Thebase plate 11 is outwardly dished toa slight extent tospace t ie central portion thereof from the diaphragm a greater distance than is provided by the annular washer 10a. lvflounted upon plate 11 isa U-shaped frame 12 comprising outwardly inclined arms 13, provided with outwardly vdirected end portions 14 disposed substantially in the same plane. Uponthe members 14 is mounted, by Vmeans of clips 15 and screws 16, an elongate, laminated, flat spring 17, comprised of a plurality of strips of metal such for example as spring steel, said spring being of a length approximately the effective diameter of-the diaphragm. y Preferably the length of the spring and the number and resilience of the laminas composing it is so chosen' that the natural period of oscillation of t-he vibrating parts kis substantially equal to that ofthe diaphragm. Attached to the under side of spring` 17 is an elongate armature 18 also laminated, if desired, and held fast on the. spring by means of hammer or striker rod 19, the threaded end of which is received in a threaded opening inthe armature, which, in turn, is held tightly engaged with the spring by a nut 2O on the projecting` end of the striker rod. Between armature 18 and spring 17 is a clipl 21 shown inperspective in Fig. 4 having a central opening 22 through which striker 19- passes and integral off-set portions 23 adapted'to embrace the laminated armature as indicated in Fig. 3, the clip also having oppositely off-setv portions 24 between which spring 17 is received. The lfunction of the clip 21 is to Vhold armature 18 always in paralleldisposition with respect to spring 17 By means Aof the cut or slot 25 in thetop of striker rod 19, `the latter may be adjusted relatively to the 'spring and the armature. This is accomplished by loosening nut 20 -upon `the frame 12, their and then turning striker rod 19 the required amount by means of a screw driver or other suitable tool inserted in slot 25.

Striker 19 as shown extends downwardly between Ielectro-maginets 26 and through openings in bot-h frame 12 and plate 11 as indicated in Fig'. 3 withits 'free'end' closely adjacent to but normally out of contact with the diaphragm 10. Electro-magnets261rest cores passing through aligned openings in the frame and base plate and being headed over beneath the latter as indicated at 27,' or otherwise suitably made fast in said plate to. permanently unite theframeand the base plate.

Means for producing' make-,and-break electrical connection through the magnets, preferably comprises a pair offcontact members adjustably supported upon a member 28 preferably integral with base 11 and oflset therefrom (Figs. 1 and The'upper contact member is supportedin properrposition by a bracket 29 (Figs. 5 and 6),-'having ya main portion of generally rectangular form having a centrally disposed elongate slot 30. in extension 31 is provided at one side of said bracket, and lying inthe plane thereof, such extension havingv an arm 31a extending first upwardly and then outwardly at sub-kV stantially 90o as indicated at V32,-the lasty named member extending laterally as shown at 33 1n a direction substantially.parallel to the plane of bracket 29, which disposes the Contact point 34 inl a plane perpendicular to.

and substantially axial of the slot 30.

he lower contact member is su'pported'by an angular bracket 35 having an elongate slot 36 similar to slot 30 of the upper meme ber and. provided with aflat spring 37 riveted as at 3S or otherwise suitably fast upon its `horizontal portion. Upon the free end of spring 37 is fixed-a contact point 39 so dis` posed that when angular supports 29 and 35 are properlyl adjusted upon the extension 28, contact points 34 and 39 are in afvertical aligned disposition'as shown in-Fig.V 3. 'The free end 37a of spring 37 extends under ar mature 1S so that when the latter isy pulled downwardly by the action of magnets 2G, the armature strikes spring 37 and breaks the contact between points 34 and 39. Brackets 29 and 35 are separated from each other and from the supporting memberQS by suitable plates 40 `of insulating material and are clamped inadjusted position by screws41.

vThe entire mechanism isfprotected from dust and moistureA by a cover'42 which has on offset annular iange fittingl in the' space between flange 9 of the horn andthe rim of base plate 11, being retained lin position by nuts 43 on the project-ing threaded ends'f bolts 14e. Thef electric circuit through the device includes a suitable source of, power (not shown),,bind-ingfpost44 (Fig. 1), conductor 45, electromagnets 26 which -are coniso l nected in series, conductor 46 (Figs. 1 and 3) which is attached to projection 3l of contact member 29, contact point 34;, contact point 39, bracket 35, screws Lll to support 28 and ground. Slot V30 in bracket 29 is not only sufficiently large to permit adjustment of this member both vertically and horizontally, but also prevents contact of such meinber with sorews'll, whereby shortcircuiting of the device is prevented. Slots 3() and 3l permit individual adjustment in two dimensions of each of' brackets Q9 and 35 by slightly loosening` screws ll, and adjustment in the third dimension is possible when necessary by using insulating plates lO of different thickness.

The diverging inclination of arms 13 of U-shaped frame l2 permits the use of spring l? of proper length to provide for the desired amplitude of vibration of the ham mer under the vibrating influence imparted by the action of the magnets and the production oiia` pleasing tone with a minimum expenditure of energy. By using a multiple or laminated spring greater flexibility may be secured than with a single spring and thus by using afgeater or lesser number of' lamina?, great nicety in adjustment of the amplitude of vibration may be obtained. At the same time, such a spring insures practical immunity 'from breakage.

The herein disclosed mechanism requires no lubrication whatever and but little if any adjustment of either the hammer or the contact points. No special mechanical or electrical knowledge is required to make either of' such adjustments if necessary, while the rigid support aiforded by the base plate and frame makes it possible to obtain uniform tone production throughout the life of the mechanism.

Having thus described the invention in a specific embodiment of the same, together with the inode of operation thereof, what we claim and desire to secure by Letters Patent of the United States is zi l. A. device of` the character described including a diaphragm, avbase plate adjacent the diaphragm but 'spaced therefrom, a vibrating striker and operating mechanism therefor secured to said base plate, said base plate having an aperture therein through which the striking mechanism operates, and said base plate further having a portion cut therefrom and bent up substantially at right angles thereto adjacent the striker mecha-l nism, said bent-up portion storming a supporting bracket for a pair of supplemental brackets, one of said supplemental brackets bearing a stationary contact and the other of said supplemental brackets bearing 'a vibrating contact having a portion projecting into the path of movement of the striker mechanism.

2. A device of the character described including a base plate, a supporting` bracket carried thereby and aV pair of supplemental brackets mounted on the supporting bracket, one of said supplemental brackets having an inwardly deflected portion bearing a contact and the other of said supplemental brackets having an outwardlyV deflected portion exten-ding in the opposite direction from the deflected portion of the first bracket and having secured 'thereto a vibrator extending inwardly toward the first bracket and provided with a contact for cooperation with the contact on the bent portion of said first bracket.

3. Ay device of the character described including a base plate', a supporting bracket carried thereby Vand apair of' supplemental brackets mounted on the supporting bracket, one of said supplemental brackets having an inwardly deflected portion bearing a contact and the other of said supplemental brackets having an outwardly deflected portion extending` in the opposite' direction from the deflected portion of the lirst bracket and having secured thereto a vibrator extending inwardly towardV the firstbracket and pro* vided with a contact for cooperation with the contact lon the bent portion of` said first bracket, said base plate havingv an electrically actuated vibratory striking mechanism mounted thereon immediately adjacent the bracket and the vibrator having a projection extending into the path of movement of said striking mechanism.

l. ln a device of the character described, a base plate bearing electrically operated vibratory striker mechanism, said base plate having. a bracket rising therefrom immediately adjacent said striker mechanism, a supplemental bracket carried by the main bracket and longitudinally adjustable with respect thereto and havinga portion extending inwardly toward the striker mechanism and a second supplemental bracket carried by the main bracket and having a portion extending away fromthe striker mechanism, said outwardly extending portion having a vibrator secured thereto and extending inwardly past the first'bracket into the path of movement of the striker mechanism, said supplemental' brackets being insulated one from the other and being provided with cooperatingcontacts, both of said supple* mental brackets having corresponding elongated slots formed therein, and common fastening devices for securingl both supplemental brackets to the main supporting bracket whereby the brackets may be simultaneously adjusted to vary the point at which the projection will be engaged by the vibrating striker mechanism and may be relatively adjusted to vary the tension of the vibrator.

5. A contact-bearing bracket for an electric horn in the form of a plate having a` relatively wide elongated slot formed therein, said plate having an upward extension terminating in an inwardly bent L-shaped portion having an electric contact at its terminus, substantially as illustrated.

6. In aidev'ice of the class described an elongate spring, a magnet, an armature arried by said spring for cooperation with said magnet, and means for alternately making and breaking a circuit through said magnet comprising points normally in contact, one of said points beingk vmounted upon a spring extendinginto the path of movement of said armature as it approaches the magnet whereby contact between vsaid points is broken upon such movement of the armature, and means whereby each of said points may be adjusted in two dimensions. ,Y Y

7. ln a device of the class described an elongate spring, a magnet, an armature secured to said spring and `cooperable with said magnet, and means f for alternately making and breaking a circuit through said Y magnet comprising points normally in contact, one of said points being 'resiliently mounted, an element movableJ with saidY last named contact Vand extending into the path of movementof the arn'iature whereby contact between said points is broken on the movement of the armature toward the magnet, and means whereby either of said points may be adjusted inreither of two dimensions, such means including slotted brackets for supporting said points.

8. In a device of the class described an elongate spring, an electro-magnet, an armature secured to said' spring and cooperable with said magnet, and means for alternately making and breaking a circuit through said magnet comprising points normally in contact, one of said points being mounted upon Va spring' having an element thereof extending into the path of movement of said armature whereby contact between said points isbroken on the movement of the armature, toward the magnet,

and means whereby either of said points may be adjusted in three dimensions, said means including angular brackets supporting said points, such brackets having elongated slots therein, spacers between said brackets, and means passing through said slots for securing the brackets to 'a fixedsupport. v Y

9. yA bracket 'for use inV connection with the Contact mechanism of an electric horn comprising v'an angle plate having a relatively wide elongated slot formed in one leg and having a vibrator secured to the outer vportion of the other leg, the intermediate portion of said other leg being formed with an ogee' bend to provide clearance for the vibrator, said vibrator extending an appreciable distance to the opposite side of the slotted portion of the plate from that to which the leg projects, substantially as illustrated. y

l0. An adjustable contact breaker mechanism for electric horns including a support and a pair of brackets adjustably mounted thereon, one'of said brackets comprising a plate member having a relatively wide elongated slot formed therein and having a terminal portion bentat right angles thereto, said bent portion being of L-shaped formation to bring its terminus substantially in line with the slotted portion of the plate but laterally displaced with respect thereto, a second bracket portion having a similar vide elongated slot formed therein, said ksecond bracket portion having an outwardly extending end and having secured to said end a vibrator extending inwardly past lthe two slotted portions of the brackets, the termini of the L portion of one bracket and of the vibrator of the other bracket being provided with contact points for cooperation one with the other, and fastening devices carried by the main supporting bracket and of less diameter than the width of the slots and spaced nearer together than the length of the slots, said fastening devices passing through the ,slots of the brackets and clampingly securing the parts in position while the eXcess'in width over the dimensions and 1 arrangement of the fastening devices permits of simultaneous adjustment of the two `supplemental brackets as a unit or relative longitudinally or transversej independent adjustment thereof, as described.

Signed by yus at Lowell, Massachusetts, this fourth day of January, 1922.

BUTLER AMES.V PHILIP J. GILIN SON 

